Thesaurus.com
Dictionary.com
Showing results for caffeine. Search instead for decaffein.
Definitions

caffeine

[ka-feen, kaf-een, kaf-ee-in] / kæˈfin, ˈkæf in, ˈkæf i ɪn /


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

To test this, the team fed fruit flies caffeine under different conditions, including varying doses, daytime versus nighttime exposure, and combinations with sleep deprivation.

From Science Daily • Mar. 31, 2026

Kirkland Signature energy drinks mimic Celsius’s look, flavors, and 200 milligrams of caffeine, causing Celsius shares to fall.

From The Wall Street Journal • Mar. 25, 2026

It was a group powered by caffeine, Johnston said, and their coffee came in handy when they needed a liquid prop to do quick demos with the prototypes to test their absorbency.

From The Wall Street Journal • Mar. 20, 2026

Coffee and tea contain compounds such as polyphenols and caffeine, which are thought to support brain health.

From Science Daily • Mar. 18, 2026

It was getting to the perfect stage of meltiness, where the sugar and caffeine came together in a glorious adrenaline spiral.

From "Far from the Tree" by Robin Benway